[fall] into a coma

to enter a state of deep unconsciousness from which a person cannot be easily awakened

After the accident, the injured motorcyclist fell into a coma.
The patient's condition deteriorated, and they fell into a coma.
The doctor explained the risks of surgery, including the possibility of falling into a coma.
The medical team worked tirelessly to revive the patient who had fallen into a coma.
He suffered a massive stroke and subsequently fell into a coma for several weeks.